When Patrick McGoohan curtailed the fourth season of Danger Man (ITV, 1960-61; 1964-67) to make The Prisoner (ITV, 1967-68), he took much of the crew with him. Others, including producer Sidney Cole and editor/second unit director John Glen, were instead re-assigned to new project 'McGill'. Like The Prisoner, it featured a fiercely independent ex-secret agent who leaves his agency under a cloud, only to find his ethics and sense of self constantly tested while still being dogged by his past. If The Prisoner turned the genre on its head, Man in a Suitcase (as McGill would become) became the toughest and most physically and emotionally violent of all ITC series.

Man in a Suitcase transcended the boundaries of the detective genre through the powerful performance by American method actor Richard Bradford. His intense, even soulful interpretation of McGill (no first name is given, though friends use the diminutive 'Mac') as a man permanently in limbo is as emotional and nakedly vulnerable as McGoohan's is cerebral and introspective. This dichotomy is finely explored in 'Day of Execution' (tx. 11/10/1967), in which anonymous villains relentlessly chisel away at McGill's identity until all that remains is his instinct for self-preservation, and in several episodes with tragic finales.

In 'Man from the Dead' (tx. 1/11/1967) we discover that McGill really is innocent, set up by his CIA superior to protect a mole in Soviet intelligence. His status as a casualty of cold war intrigue is reflected in episodes like 'Somebody Loses, Somebody... Wins? (tx. 31/1/1968), the directorial debut of future James Bond director John Glen, and 'The Boston Square' (tx. 24/1/1968) a virtual remake of the Danger Man episode 'It's Up To The Lady' (tx. 23/2/1965). While the pursuit to Greece of a man planning on defecting via Albania stays the same in both episodes, the crucial difference lies in how the plot is crafted to reflect McGill's own circumstances - the man is a mole being planted behind the iron curtain, but his fate remains uncertain.

Highly susceptible to the ladies, McGill is always alone by story's end, often beaten and frequently unpaid. Although Bradford's is the only recurring character, many of the supporting actors appeared twice in different roles, among them Colin Blakeley, Donald Sutherland, Charles Lloyd Pack, Frank Gatlif and Philip Madoc.